https://www.cia.gov/library/readingroom/document/cia-rdp79b00752a000300070001-8

The C.I.A. classified a book on earth's catastrophe cycle and crust displacement in 1966. With the focus and publicity of the topic at the time, why classify THIS one, wait so long to release it, and so-heavily sanitize the document?

https://m.youtube.com/watch?v=wvjJqIXYT1wl